To work around the problem renaming indexed files in Windows 10, I pause the indexer (in Control Panel > Indexing Options).
The 'Pause' button seems to force the indexer-search service to sleep for 15 minutes (?)
To resume the indexer - before the 15 minutes period ends - there is no 'Resume' button;
Look at Richard's 2017 answer here: https://answers.microsoft.com/en-us/windows/forum/all/how-to-unpause-indexing-in-windows-10/bbb6b65c-c7cb-4fde-8c87-f6dd44fb6d81
My workaround for this next problem is to restart the 'Windows Search' service (in Services - services.msc)
Note: I guess the service named 'Windows Search' performs both 'indexing' and 'search' functionality. Who knows?